This invention relates to a recording/reproduction apparatus and method as well as a recording medium, and more particularly to a recording/reproduction apparatus and method as well as a recording medium suitable for use to seamlessly reproduce discontinuous AV data read out by random accessing.
In recent years, a DVD-RAM (Digital Versatile Disk-Random Access Memory) and so forth have been developed as a medium onto and from which data can be recorded and reproduced. Such large capacity media as a DVD-RAM are expected very much as media onto which a digital AV (Audio Visual) signal such as a video signal is to be recorded.
As a supply source of a digital AV signal to be recorded onto a DVD-RAM or the like, an AV signal recorded on a VHS cassette tape, an 8-mm tape and so forth which are existing recording media, an AV signal as a broadcasting signal of digital satellite broadcasting, digital ground wave broadcasting, digital cable television broadcasting or the like, or a like AV signal is available.
A digital video signal supplied from any source described above is normally in a form compressed and coded in accordance with the MPEG (Moving Picture Experts Group) 2 system. Accordingly, when a digital video signal supplied from any source is recorded onto a DVD-RAM or the like, an AV signal compressed and coded in accordance with the MPEG2 system must be decoded once and then encoded in accordance with the MPEG2 system and recorded onto the optical disk. However, where an AV signal in a compressed and coded state is decoded and encoded again in this manner, the quality of the AV signal is deteriorated significantly.
Therefore, in order to minimize the deterioration of the quality of an AV signal, it is investigated to record an AV signal in a compressed and coded state supplied from any source in the form of a bit stream as supplied onto a DVD-RAM or the like without encoding and decoding the AV signal. In other words, it is investigated to use a DVD-RAM or the like as a data streamer.
A disk medium such as a DVD-RAM allows high speed random accessing thereto. Thus, it is convenient if this fact can be utilized to reproduce a bit stream recorded on a DVD-RAM or the like in an order different from the order in which it is recorded. To designate a reproduction order is a kind of editing, and designation of a reproduction order is performed without any change in arrangement of the bit stream recorded on the disk. In the following, such editing as just described is described as nondestructive editing.
However, since the arrangement of a bit stream on a disk medium is not necessarily in an optimized state for nondestructive editing, there is a subject that, when nondestructive editing is actually executed, the AV signal is interrupted at a changeover point of the bit stream and so forth.